XML 58 R2.htm IDEA: XBRL DOCUMENT
v3.23.1

Pay vs Performance Disclosure | 12 Months Ended
--- | ---
Dec. 31, 2022 USD ($) $ / shares | Dec. 31, 2021 USD ($) $ / shares | Dec. 31, 2020 USD ($) $ / shares | Dec. 31, 2019 USD ($)
Pay vs Performance Disclosure [Table] |  |  |  |
Pay vs Performance [Table Text Block] |
Year 1 | Summary Compensation Table Total Compensation for Principal Executive Officer (PEO)2 ($) | Compensation Actually Paid to PEO 3 ($) | Average Summary Compensation Table Total Compensation for Non-PEO Named Executive Officers 4 ($) | Average Compensation Actually Paid to Non-PEO Named Executive Officers 5 ($) | Value of initial fixed $100 investment based on: | Net Income 8 (in thousands) ($) | Company Selected Measure - Earnings per Share 9 ($)
Total Stockholder Return 6 ($) | Peer Group Total Stockholder Return 7 ($)
2022 | 5,257,289 |  | 5,644,274 |  | 1,901,639 |  | 1,998,863 |  | 111.98 |  | 123.90 |  | 367,489 |  | 1.81 |
2021 | 5,210,467 |  | 7,143,972 |  | 1,810,584 |  | 2,273,834 |  | 110.37 |  | 128.00 |  | 378,131 |  | 1.87 |
2020 | 6,423,410 |  | 5,664,783 |  | 2,042,921 |  | 1,901,274 |  | 91.69 |  | 101.04 |  | 390,205 |  | 1.95 |
Named Executive Officers, Footnote [Text Block] | Our PEO for years 2020, 2021 and 2022 was David L. Goodin. Our non-PEO named executive officers (NEO) for 2020, 2021 and 2022 were Jason L. Vollmer, David C. Barney, Jeffrey S. Thiede and Nicole A. Kivisto. |  |  |
Peer Group Issuers, Footnote [Text Block] | Represents the value of $100 invested in the compensation peer group company stock on December 31, 2019 as of December 31.2020, December 31, 2021 and December 31, 2022 assuming dividends are reinvested in the compensation peer group stock at the frequency paid. Returns of each peer group company are weighted according to the peer group company’s market capitalization at the beginning of the period. Our compensation benchmarking peer group companies for 2020, 2021 and 2022 included:
| 2020 | 2021 | 2022 |
| Alliant Energy | Alliant Energy | Alliant Energy |
| Ameren Corporation | Ameren Corporation | Ameren Corporation |
| Atmos Energy Corporation | Atmos Energy Corporation | Atmos Energy Corporation |
| Black Hills Corporation | Black Hills Corporation | Black Hills Corporation |
| CMS Energy Corporation | CMS Energy Corporation | CMS Energy Corporation |
| Dycom Industries, Inc. | Dycom Industries, Inc. | Dycom Industries, Inc. |
| EMCOR Group, Inc. | EMCOR Group, Inc. | EMCOR Group, Inc. |
| Evergy, Inc. | Evergy, Inc. | Evergy, Inc. |
| Granite Construction Incorporated | Granite Construction Incorporated | Granite Construction Incorporated |
| Jacobs Engineering Group Inc. | Jacobs Engineering Group Inc.* | KRB, Inc. |
| KRB, Inc. | KRB, Inc. | Martin Marietta Materials, Inc. |
| Martin Marietta Materials, Inc. | Martin Marietta Materials, Inc. | MasTec, Inc. |
| MasTec, Inc. | MasTec, Inc. | MYR Group, Inc.* |
| NiSource Inc. | NiSource Inc. | NiSource Inc. |
| Pinnacle West Capital Corporation | Pinnacle West Capital Corporation | Pinnacle West Capital Corporation |
| Portland General Electric Company | Portland General Electric Company | Portland General Electric Company |
| Quanta Services, Inc. | Quanta Services, Inc. | Quanta Services, Inc. |
| Southwest Gas Holdings, Inc. | Southwest Gas Holdings, Inc. | Southwest Gas Holdings, Inc. |
| Summit Materials, Inc. | Summit Materials, Inc. | Summit Materials, Inc. |
| Vulcan Materials Company | Vulcan Materials Company | Vulcan Materials Company |
| WEC Energy Group, Inc. | WEC Energy Group, Inc. | WEC Energy Group, Inc. |
| *Jacobs Engineering Group, Inc. was replaced with MYR Group Inc. in 2022 due to size. Total stockholder return for the peer group companies for 12/31/2020, 12/31/2021 and 12/31/2022 were as follows |
|  | 12/31/2019 | 12/31/2020 | 12/31/2021 | 12/31/2022 |
| Peer group with Jacobs Engineering Group Inc. | $ | 100.00 |  | $ | 101.04 |  | $ | 128.00 |  | $ | 124.22 |  |
| Peer group with MYR Group, Inc. | $ | 100.00 |  | $ | 100.01 |  | $ | 126.85 |  | $ | 123.90 |  |
PEO Total Compensation Amount | $ 5,257,289 | $ 5,210,467 | $ 6,423,410 |
PEO Actually Paid Compensation Amount | 5,644,274 | 7,143,972 | 5,664,783 |
Non-PEO NEO Average Total Compensation Amount | 1,901,639 | 1,810,584 | 2,042,921 |
Non-PEO NEO Average Compensation Actually Paid Amount | $ 1,998,863 | 2,273,834 | 1,901,274 |
Compensation Actually Paid vs. Total Shareholder Return [Text Block] | CAP vs. TSR Our TSR is a reflection of our stock price and dividends paid over a period of time and is important to stockholders as it measures the performance of an investment in our company stock in the marketplace. The following charts depicts the PEO and average non-PEO named executive officer CAP compared to the value of $100 invested in company and peer company stock on December 31, 2019 as of December 31, 2020, December 31, 2021 and December 31, 2022 assuming dividends are reinvested in company stock at the frequency paid. |  |  |
Compensation Actually Paid vs. Net Income [Text Block] | CAP vs. Net Income The following charts depicts the PEO and average non-PEO NEO CAP compared to the company’s net income for 2020, 2021 and 2022. CAP vs. EPS The following charts depicts the PEO and average non-PEO named executive officer CAP compared to the company’s EPS for 2020, 2021 and 2022. |  |  |
Compensation Actually Paid vs. Company Selected Measure [Text Block] |  |  |  |
Total Shareholder Return Amount | $ 111.98 | 110.37 | 91.69 |
Net Income (Loss) | $ 367,489,000 | $ 378,131,000 | $ 390,205,000 |
Company Selected Measure Amount | $ / shares | 1.81 | 1.87 | 1.95 |
PEO Name | David L. Goodin |  |  |
Measure [Axis]: 1 |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Measure Name | Earnings per Share |  |  |
Measure [Axis]: 2 |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Measure Name | Earnings Growth from Continuing Operations |  |  |
Measure [Axis]: 3 |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Measure Name | Relative Total Stockholder Return |  |  |
MYR Group, Inc. [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Peer Group Total Shareholder Return Amount | $ 123.90 | $ 126.85 | $ 100.01 | $ 100.00
Jacobs Engineering Group Inc. [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Peer Group Total Shareholder Return Amount | 124.22 | 128.00 | 101.04 | $ 100.00
PEO [Member] | Equity Award Values Reported in the SCT [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 3,247,775 | 3,222,639 | 2,974,497 |
PEO [Member] | Equity Award Adjustments [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 3,634,760 | 5,156,144 | 2,651,451 |
PEO [Member] | Changes to Pension Reported in SCT [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 0 | 0 | 435,581 |
PEO [Member] | Aggregated Service Cost and Prior Service Cost [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 0 | 0 | 0 |
PEO [Member] | YE Value of Equity Awards Granted during year which are Unvested [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 3,665,234 | 3,586,652 | 2,402,446 |
PEO [Member] | Y o Y Change in Value of Equity Awards Granted in Prior Years which are Unvested [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | (198,017) | (90,005) | (557,760) |
PEO [Member] | Value at Vesting Date of Equity Awards Granted and Vesting in the Year [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 0 | 0 | 0 |
PEO [Member] | Y o Y Change in Value of Equity Awards Granted in prior years which Vest in Year [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 167,543 | 1,659,497 | 806,765 |
PEO [Member] | PYE Value of Equity Awards that Failed to Meet Vesting Conditions [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 0 |  | 0 |
PEO [Member] | Value of Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Value or Total Compensation [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 0 | 0 | 0 |
Non-PEO NEO [Member] | Equity Award Values Reported in the SCT [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 862,681 | 870,757 | 707,370 |
Non-PEO NEO [Member] | Equity Award Adjustments [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 959,905 | 1,334,007 | 634,637 |
Non-PEO NEO [Member] | Changes to Pension Reported in SCT [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 0 | 0 | 68,914 |
Non-PEO NEO [Member] | Aggregated Service Cost and Prior Service Cost [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 0 | 0 | 0 |
Non-PEO NEO [Member] | YE Value of Equity Awards Granted during year which are Unvested [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 973,569 | 969,113 | 571,330 |
Non-PEO NEO [Member] | Y o Y Change in Value of Equity Awards Granted in Prior Years which are Unvested [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | (53,505) | (21,403) | (129,852) |
Non-PEO NEO [Member] | Value at Vesting Date of Equity Awards Granted and Vesting in the Year [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 0 | 0 | 0 |
Non-PEO NEO [Member] | Y o Y Change in Value of Equity Awards Granted in prior years which Vest in Year [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 39,841 | 386,297 | 193,159 |
Non-PEO NEO [Member] | PYE Value of Equity Awards that Failed to Meet Vesting Conditions [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | 0 | 0 | 0 |
Non-PEO NEO [Member] | Value of Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Value or Total Compensation [Member] |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |
Adjustment to Compensation Amount | $ 0 | $ 0 | $ 0 |

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 3 + Details
Name: | ecd_AdjToCompAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph vi + Details
Name: | ecd_CoSelectedMeasureAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 5 -Subparagraph iii + Details
Name: | ecd_CompActuallyPaidVsCoSelectedMeasureTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 5 -Subparagraph ii + Details
Name: | ecd_CompActuallyPaidVsNetIncomeTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 5 -Subparagraph i + Details
Name: | ecd_CompActuallyPaidVsTotalShareholderRtnTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph vi + Details
Name: | ecd_MeasureName
Namespace Prefix: | ecd_
Data Type: | xbrli:normalizedStringItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 3 + Details
Name: | ecd_NamedExecutiveOfficersFnTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph iii + Details
Name: | ecd_NonPeoNeoAvgCompActuallyPaidAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph ii + Details
Name: | ecd_NonPeoNeoAvgTotalCompAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph iv + Details
Name: | ecd_PeerGroupIssuersFnTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph iv + Details
Name: | ecd_PeerGroupTotalShareholderRtnAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph iii + Details
Name: | ecd_PeoActuallyPaidCompAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 3 + Details
Name: | ecd_PeoName
Namespace Prefix: | ecd_
Data Type: | xbrli:normalizedStringItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph ii + Details
Name: | ecd_PeoTotalCompAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 1 + Details
Name: | ecd_PvpTable
Namespace Prefix: | ecd_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 1 + Details
Name: | ecd_PvpTableTextBlock
Namespace Prefix: | ecd_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-K -Number 229 -Section 402 -Subsection v -Paragraph 2 -Subparagraph iv + Details
Name: | ecd_TotalShareholderRtnAmt
Namespace Prefix: | ecd_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(22)) -URI https://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (f) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 4 -URI https://asc.fasb.org/extlink&oid=124431687&loc=d3e22595-107794 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(18)) -URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 65 -Paragraph 1 -Subparagraph (f) -URI https://asc.fasb.org/extlink&oid=126732423&loc=SL123482106-238011 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 50 -Paragraph 6 -URI https://asc.fasb.org/extlink&oid=124431353&loc=SL124452729-227067 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(5)) -URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756 Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(20)) -URI https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227 Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI https://asc.fasb.org/extlink&oid=124431687&loc=d3e22499-107794 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(iv)) -URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(iii)(A)) -URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(i)) -URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(i)) -URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI https://asc.fasb.org/extlink&oid=124431687&loc=d3e22663-107794 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(iv)) -URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756 Reference 17: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(4)(ii)) -URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (f) -URI https://asc.fasb.org/extlink&oid=123596393&loc=d3e14064-108612 Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=124431687&loc=d3e22583-107794 Reference 20: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(g)(1)(ii)) -URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 60B -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126958026&loc=SL5780133-109256 Reference 22: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 Reference 23: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 8 -URI https://asc.fasb.org/extlink&oid=124431687&loc=d3e22658-107794 Reference 24: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126968391&loc=SL7669619-108580 Reference 25: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 31 -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8924-108599 Reference 26: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794 Reference 27: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=124431687&loc=d3e22694-107794 Reference 28: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 7 -URI https://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760 Reference 29: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126968391&loc=SL7669625-108580 Reference 30: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599 Reference 31: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1A -Subparagraph (SX 210.13-01(a)(5)) -URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442526-122756 Reference 32: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(iii)(B)) -URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756 Reference 33: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section S99 -Paragraph 1B -Subparagraph (SX 210.13-02(a)(4)(iii)(A)) -URI https://asc.fasb.org/extlink&oid=126975872&loc=SL124442552-122756 Reference 34: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599 Reference 35: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599 + Details
Name: | us-gaap_NetIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | ecd_MeasureAxis=1
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_MeasureAxis=2
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_MeasureAxis=3
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_IndividualAxis=mdu_MYRGroupIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_IndividualAxis=mdu_JacobsEngineeringGroupIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_ExecutiveCategoryAxis=ecd_PeoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=mdu_EquityAwardValuesReportedInTheSCTMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=mdu_EquityAwardAdjustmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=mdu_ChangesToPensionReportedInSCTMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=mdu_AggregatedServiceCostAndPriorServiceCostMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=mdu_YEValueOfEquityAwardsGrantedDuringYearWhichAreUnvestedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=mdu_YOYChangeInValueOfEquityAwardsGrantedInPriorYearsWhichAreUnvestedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=mdu_ValueAtVestingDateOfEquityAwardsGrantedAndVestingInTheYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=mdu_YOYChangeInValueOfEquityAwardsGrantedInPriorYearsWhichVestInYearMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=mdu_PYEValueOfEquityAwardsThatFailedToMeetVestingConditionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_AdjToCompAxis=mdu_ValueOfDividendsOrOtherEarningsPaidOnEquityAwardsNotOtherwiseReflectedInValueOrTotalCompensationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ecd_ExecutiveCategoryAxis=ecd_NonPeoNeoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |